//增
procedure TForm1.btnAddClick(Sender: TObject);
begin
ADOQuery1.Close;
ADOQuery1.SQL.Clear;
ADOQuery1.SQL.Add('select * from AZZ where 排名=(''' + Edit1.Text + ''')');
ADOQuery1.Open;
//if ADOQuery1.IsEmpty then
??????????????????????????
if ADOQuery1.RecordCount = 0 then //如果记录为空....做判断
begin
ADOQuery1.Close;
ADOQuery1.SQL.Clear;
ADOQuery1.SQL.Add('insert into AZZ(排名,名称,网址,国家) values (''' + Edit1.Text + ''', ''' + Edit2.Text + ''',''' + Edit3.Text + ''',''' + Edit4.Text + ''')');
if (trim(Edit1.text)='') or (trim(Edit2.text)='') or (trim(Edit3.text)='') or (trim(Edit4.text)='') then
begin
showMessage('有数据输入为空,请重新输入!');
exit //强制跳出if语句
end
else
begin
showMessage('数据添加成功!');
end;
ADOQuery1.ExecSQL;
ADOQuery1.Close;
ADOQuery1.SQL.Clear;
ADOQuery1.SQL.Add('select * from AZZ');
ADOQuery1.Open;
end
else
begin
showmessage('您输入的排名已经存在,请重新输入!');
end;
end;